A photovoltaic installation is divided into one or more units. Each unit includes a number of solar components and a transfer point. The solar components may be configured e.g. as solar modules, each of which includes a number of solar cells with a glazed cover panel and a mounting frame. In other forms, the solar components may be configured differently, for example in the form of a number of solar modules or a number of solar cells. The solar components may be secured rigidly in a predetermined orientation, or may be arranged to track the position of the sun, either individually or in combination. In the case of a stationary arrangement of solar components, the transfer points of units observe a uniform pattern, and there is no variation in the design of units, such that the routing of cables within each unit may be arranged in a uniform manner.
However, where solar components track the sun, a grouping of solar components is governed, not only by electrical criteria, but also by mechanical criteria. The object, for example, is that as many solar components as possible should track the sun via a common drive system. Tracking involves the rotation of solar components around an axis.
Accordingly, the grouping of solar components in the units of a photovoltaic installation may pose a complex problem. The routing of cables between the solar components and a transfer point in each unit also poses a subsidiary problem. In general, the solar components of each unit are arranged individually, and an individual transfer point is provided. The laying of cables is governed by rules, for example, solar components may be quadrilateral, whereby cables are only to be laid parallel to the edges of solar components. Accordingly, the edges of solar components are arranged in parallel pairs, such that cables may only be routed in two directions, at right-angles to each other. A further rule may dictate that cables are only to be laid outside the perimeter of solar components. In a large photovoltaic installation, horizontally-routed cable sections are embedded in the ground. To this end, cable ducts are provided, for the accommodation of one or more cables, running from one of the solar components to the transfer point.
For electrical reasons, the cables between the individual solar components and the transfer point of each unit are kept as short as possible. At the same time, expenditure for the provision of cable ducts is kept as low as possible, in order to save costs.
For an individual unit in the photovoltaic installation, this problem is resolved forthwith by the execution of a first act, in which all potential cabling options are constituted in accordance with existing rules, and a second act for the selection of those cabling options that provide the optimum fulfillment of the criteria specified. An exhaustive optimization of all the cable routing options constituted may be executed, for example, via a mixed-integer program, which identifies an optimum solution.
However, the workload associated with the determination of optimum cable routes for several tens, several hundred or even several thousand units may be so great that even a state-of-the art computing facility is not capable of defining optimized solutions for all units within an acceptable time. Accordingly, a run-through of multiple planning variants for a planned photovoltaic installation, or a rapid response to a change in project requirements, is not possible.